Vulnerability to physical inactivity: evidence of content validity and response processes

ABSTRACT Objective: To analyze content validity evidence and response processes of a bank of items for measuring vulnerability to physical inactivity in adults. Method: Methodological study, with 13 specialists and 46 representatives of the target population. The Content Validity Index (CVI) and binomial test were calculated; data obtained through validity based on response processes were collected through interviews. Results: Of the 105 constructed items, 16 were excluded (CVI<0.78); 89 items showed agreement <80% in the psychometric criteria, being modified. Of the 101 items that remained (CVI>0.78), 34 were changed and 4 were deleted after evaluating the evidence of response processes. In the end, 97 items remained, with a global CVI of 0.92, organized into two dimensions: Subject (CVI=0.91) and Social (CVI=0.94). Conclusion: The items presented adequate parameters and evidence of validity; and can subsidize the construction of instruments that consider the subject’s and social vulnerability in understanding physical inactivity.


INTRODUCTION
One of the essential health elements for the healthy development and quality of life of people is physical activity (1) , however, there is a high prevalence of physical inactivity, defined here as the condition of not meeting the recommendations for moderate to vigorous intensity physical activity (2)(3) .Due to its individual and social impact (4)(5) , efforts have been made to include the regular practice of physical activities in the daily lives of people around the world (6) and in Brazil (7) .
Without ignoring individual aspects, such as beliefs, affections and feelings, social inequalities have been identified as strong influencers on adherence to physical activity, especially during leisure.Some socially and economically less privileged groups tend to be at a notable disadvantage in terms of possibilities and options for regular practice of physical activities (8)(9) .Thus, analyzing the main vulnerability factors that contribute to the outcome "physical inactivity" is a promising means for planning and implementing strategies to promote physical activity for the health of different populations (10)(11) .
The vulnerability approach has been used to discover how the interaction between individual aspects and cultural and social dynamics can increase people's susceptibility to harm, threats or dangers (10) .In this sense, vulnerability to physical inactivity is understood as a condition generated through the interaction between elements of multiple dynamic relationships of the subject in their social context, which produces greater precariousness and exposure to unfavorable factors of physical activity for health, without means of coping (12) .
The Subject Dimension of vulnerability to physical inactivity shows how much personal aspects can increase the chances of physical inactivity, understood here as the subject as a producer and as a product of the power relations existing in society.The Social Dimension reflects the understanding of physical inactivity based on the subject's multiple collective and contextual elements (11)(12) .
Currently, there are measurement instruments that assess aspects of physical (in)activity, such as the level of physical activity (13)(14) and perception of barriers to practice (15) , however, they do not understand this construct in its entirety and complexity.Most evaluate only a few elements from an individual perspective, without considering the subjectivities and the questioning of health inequalities that involve some population groups.Thus, there is still a need for instruments, with evidence of validity, that enable sufficient and reliable data to understand contemporary, individual, collective, and contextual attributes, in an articulated way -for example, those understood from the perspective of subject and social vulnerabilities.
From this perspective, a bank of items, that is, a set of evaluative questions, with evidence of the validity of its content by specialists and an approach to aspects of vulnerability in the context of physical inactivity, enables the development of measurement instruments, which help in the understanding the level of susceptibility to physical inactivity and identifying personal and social factors that influence this outcome.With these results, specific health intervention strategies can be proposed, according to the identified need.

OBJECTIVE
To analyze content validity evidence and response processes of a bank of items for measuring vulnerability to physical inactivity in adults.

Ethical aspects
This study was approved by the Ethics Committee of the State University of Ceará and developed according to the ethical precepts contained in Resolution 466/2012 of the National Health Council of Brazil (16) .Free and Informed Consent was obtained from all individuals involved in the study, in writing (target population) and online (experts).

Study design, period, and place
Methodological study, based on the first of the three poles of psychometrics for the development and validation of instruments (theoretical, empirical and analytical) (17) .Therefore, it refers to the theoretical pole, which includes the phases of construction and evidence of content validity and response processes: 1) construction of the item bank based on the constitutive and operational definitions of the studied construct; 2) search for sources of evidence of validity of the content of the items according to experts; 3) response processes.
Content validation took place in a virtual environment, covering seven states in Brazil.The validity based on the response processes took place in September 2021, in the city of Juazeiro do Norte, located in the central area of the Metropolitan Region of Cariri, in the south of the state of Ceará.

Population or sample; inclusion and exclusion criteria
For the content validation stage, 25 specialists were invited (17) , with academic training, professional activity and scientific production and consistent with the subject studied, in addition to knowledge about methodological studies.For the phase of evidence based on the response processes, the target population of this study was considered, namely adults, aged between 18 and 59 years, as indicated in public policies to promote physical activity at the national level (7) .Thus, a representative sample of all strata of this population was selected: 46 adults of both genders, residing in the collection site for at least six months.Institutionalized adults, unable to communicate and who withdrew from participating in the research were excluded.

Study protocol
The definition of the construct "Vulnerability to Physical Inactivity" and the elucidation of its dimensionality, constitutive elements, as well as constitutive and operational definitions of its markers were given through a literature review, critical reflection of the authors and evidence of validity of its content by specialists (12) .To define the behaviors and attitudes through which this construct is expressed, an item bank was created, based on psychometric criteria recommended by Pasquali (17) : relevance, precision, objectivity, simplicity, clarity, variety, modality, typicality, credibility , breadth and balance.
In content validation, the following criteria were used to select specialists: academic background, knowledge about methodological studies, scientific production, and professional performance.The selection took place through consultation with the Lattes Platform and the national database of the Coordination for the Improvement of Higher Education Personnel (CAPES), and the specialists were contacted and invited to participate in the study by email, with the indication of other professionals also being required with similar profile.
After acceptance, an email was sent with the Free and Informed Consent Form (FICF), an evaluation instrument prepared by the author and instructions for completing it.We chose to develop this instrument because of the quantity and specificity of the items to be evaluated and the established psychometric criteria.It is a spreadsheet created in the Microsoft Excel ® program, with the items and criteria considered in the evaluation, in addition to spaces for inclusion of possible specialist suggestions.
The 25 experts invited had 15 to 20 days to judge the relevance and pertinence of the items in relation to the studied construct.This evaluation focused on the objectivity, simplicity, clarity, precision, and relevance of the items, analyzed on a four-point ordinal scale: 1) not indicative; 2) not very indicative; 3) indicative; 4) very indicative.Then, the data were analyzed by calculating the Content Validity Index (CVI) and the agreement on the psychometric criteria (17) .
Next, an attempt was made to analyze the understanding of the items for all segments of the population for which they were developed.In this way, the response processes were performed, as evidence that gathers arguments denoting the consistencies between the responses and the processes for which the proposed tasks are established (18) .The set of items was applied in September 2021, to people from the lowest to highest levels of education (considering years of study and grade) of the target population.
The 46 adults were randomly selected and invited to participate in the research voluntarily.Items were evaluated for understandability of words, terms, meaning and format.The evaluation of the items in the response processes was carried out in the form of an individual interview, and the researcher observed the participants' reaction to each of the items, identifying difficulties and weaknesses.Each suggestion given regarding the elimination of an item or the best way of presenting it was recorded in writing for later analysis and amendment.
It should be noted that social (age, gender, city/state), academic (schooling, training) and professional information (exercise paid activity, length of profession, place of work) were collected from specialists and target audience.
In order to complement the analysis, evidence based on the response processes was investigated, to understand how people interpreted and interacted with the items and, thus, identify the possibility of the instrument being accepted and used as a support tool for decision making.

Analysis of results and statistics
For data analysis, the CVI was calculated using the formula: number of responses "3" and "4" divided by the total number of responses (19) .Those that received a score of 1 or 2 were revised or eliminated.Item CVI > 0.80 and mean total and global CVI > 0.90 were considered excellent.The variables were categorized to perform the exact binomial distribution test for small samples, considering a significance level of 5% and a 0.80 proportion of agreement to estimate the statistical reliability of the CVIs.
The psychometric criteria were assessed by a minimum agreement of 80% among specialists (Table 1), in addition to cultural and relative aspects of content validity (20)(21) .
As for the evidence based on the response processes, each item was read by the researcher during the interviews, so that the participants informed their understanding of what was asked and, thus, proceeded with the answer and possible suggestions.A written record was made of all the suggestions given by the participants regarding the elimination or better presentation of the items.In case of recurring doubts, the item has been reformulated or eliminated (17) .

RESULTS
The construction of the items considered the pre-defined criteria and resulted in 105 in total (56 from the Subject Dimension and 49 from the Social Dimension).To validate their content, 25 experts were invited.Of these, 20 agreed to participate in the study, and 13 returned the completed instrument within the requested time.The 13 specialists who acted as judges were health professionals with proven professional experience, including physical education professionals and nurses; researchers with publications on the subject; and from seven Brazilian states (Ceará, Pernambuco, Amazonas, Piauí, Bahia, Rio de Janeiro, and Santa Catarina).
In all, 16 items were excluded because they were not considered representative of the latent trait studied, obtaining a CVI < 0.78.Of the 89 items that remained, those with ≤ 80% interexpert agreement on psychometric criteria were modified.Such modifications included substituting terms and words for greater clarity and simplicity.To ensure greater objectivity, precision and relevance, there was also the agglutination of items to form a single one, and the separation of items, to form more than one, resulting in a total of 101 at the end of the process.An example is item 1 (Subject Dimension), which was changed from "What age group does your age include?"; items 26 and 27 (Subject Dimension), which were modified from "How much do you feel able to exercise in the presence of unfavorable physical sensations, such as tiredness, pain or discomfort?"; and item 29 (Social Dimension), modified from "In the neighborhood where you live and in the immediate vicinity, is there little availability of public services (health units/posts, post office, police station, airport)?"and "In the neighborhood where you live and in the immediate vicinity, are there few establishments that provide essential and non-essential services to the community (shopping centers, markets, banks, restaurants, pharmacy, religious temples, beauty centers, schools and the like)?".
According to Chart 1 and 2, after these analyses, 101 items remained, with 84 modified due to the judgment of the psychometric criteria.Of these, 50 items were classified in the Subject Dimension; and 51, in the Social Dimension.The analysis of the binomial test shows that none of the items presented significant disagreements between the judges.The total CVI was 0.91 in the subject dimension; and 0.94, in the social dimension.The overall CVI, which considers the entire set of questions, was 0.92.
The 101 items that had their content validated by experts were directed to validity based on response processes.This phase had the participation of 46 adults, with a mean age of 37.32 (+ 10.05) years; and minimum and maximum age of 18 and 58 years, respectively.People from all levels of education participated: 7 (15.2%)were only literate; 7 (15.2%)had only elementary education; 15 (32.6%), high school; 10 (21.7%), higher education; and 7 (15.2%),postgraduate.
People with different professions/occupations were included, such as teachers, lawyers, nurses, health agents, commercial workers, students, day laborers, farmers, painters, drivers, caregivers of the elderly and children, as well as unemployed people.In all, the majority were female (58.7%), brown (56.5%), single (43.5%), had an income of up to one minimum wage (60.9%) and practiced physical activity during leisure (56.5%).
The evaluation of the items based on the response processes, in the form of an individual interview, revealed that 35 of them needed changes to become more understandable, especially for the lower strata of the population (Chart 3).In some items, few word or term changes were made (7, 21, 22, 23, 27, 34, 37, 44, 46  others, the structure of the question was changed (6, 9, 10, 41, 42 -Subject Dimension; 18, 23, 25, 47, 48, 49 -Social Dimension).
In addition, some items had to be eliminated due to their inadequacy and lack of understanding by the population, even after some adjustments and explanations (50 -Subject Dimension; 36 -Social Dimension) or because they were considered redundant in the face of the set of items (38 -Dimension Subject; 33 Social Dimension).
I think these two questions [38 and 39] refer to the same thing.Because having a serious injury is already a negative experience.I could just leave 39, because it already includes all the possibilities.(Person 39) You ask if my house is close to these places [33], but you asked before if my neighborhood had a square, park, gym, court [30, 31,  32]  In the end, the entire process resulted in the permanence of 97 items (with 48 in the Subject Dimension and 49 in the Social Dimension), with evidence of content validation and based on the response processes.Therefore, these were considered valid for the representation of the studied latent trait.

DISCUSSION
The present study presents a database with 97 items for measuring vulnerability to physical inactivity in adults, organized into two dimensions (Subject and Social), with appropriate parameters and validity evidence.
In general, the validation process is a judgment about the congruence between the latent trait and its physical representation.It refers to a measure based on the evaluation of the subjects and content addressed in each item of an instrument (20) .This, when properly developed, can influence decisions about care, interventions, and policies.To do so, it draws on the relevant literature, the researcher's experience, the opinion of specialists in the area, content analysis, state of the art and characteristics of the context (22) .
The construction of these evaluated items was based on theoretical reflection on issues of vulnerabilities and inequities in health and on the elucidation of the dimensionality and the constitutive elements of vulnerability to physical inactivity (12) .Such reflections were anchored in evidence from national and international studies, obtained through a scope review about intervening factors in physical inactivity, whose protocol is registered in an open platform (23) .This process was complemented by the knowledge of specialists working in different regions, to ensure the coverage of aspects and language that consider Brazilian cultural diversity.These evaluated the representativeness of the studied latent trait and produced evidence of validity of its content.
In this process, some items were excluded because they did not reach a consensus among experts regarding their representativeness in the latent trait.As for the judgment of the psychometric criteria, most of the items that remained underwent changes to meet the criteria to which they were submitted (objectivity, simplicity, clarity, precision, relevance).
The reflection of the behavioral paradigm was noted, as most of the validated items refer to individual aspects, which touch biological, psychological, and cognitive factors.However, a social understanding of the phenomenon also emerged, as some items about the economic, political, and environmental context were also validated.
This fact is linked to discussions that centralize new contexts of thought supported by social paradigms present in the current situation.Much has been discussed about the influence of social inequalities on adherence to body practices and physical activities, in which scenario some population groups are at a notable disadvantage (8) .Such inequalities are established in several health indicators, especially when innovations appear in actions to promote leisure physical activities, which tend to reach the most socially and economically privileged (9) .
Given this evidence, the items presented include a range of these variables and can be understood in a two-dimensional format (Subject and Social), by recognizing the dynamic and interrelational character of the constituent elements of the subject's vulnerability and social vulnerability.The Subject Dimension refers to the elements formed based on intersubjective relationships, in which the freedom of tension between knowledge and power weighs, which makes self-recreation possible.The Social Dimension refers to what the different means of interaction of the subject with others presuppose, based on the scenario in which the recognition and expression of the being is possible (11) .
Among the various existing approaches (31)(32) , vulnerability analysis refers to the way in which individual aspects interact with cultural and social dynamics to produce conditions that increase the chances of threats and dangers materializing (10) .By considering the negative impact of physical inactivity on the health of populations (4)(5) , the aim is to understand how the connection between the various personal and contextual aspects can increase the chances of physical inactivity at an individual and collective level.
Faced with the complexity of interactions involving physical inactivity, it is necessary that, in addition to behavioral aspects, aspects of vulnerability also be considered, since it is recognized that certain unfavorable individual, environmental and social conditions, combined with the fragility in these difficulties, 10 of Vulnerability to physical inactivity: evidence of content validity and response processes Pereira DS, Florêncio RS, Cestari VRF, Moreira TMM.
limit the choices of people and make them more susceptible to physical inactivity (12) .Such vulnerability conditions need to be considered when assessing the situation of populations for effective planning and development of actions to combat physical inactivity.This applies, especially, to multidisciplinary strategies developed in health services, for populations with or without non-communicable communicable chronic diseases (33) .In addition, such elements help in better understanding, review, application, and improvement of the nursing diagnosis "Sedentary Lifestyle", included in the North American Nursing Diagnosis Association, in 2004 (34) .
Evidence of validity based on the response processes could ensure the comprehensibility of the items for the lower strata of the population and avoid inappropriate language.Of the changed items, most underwent replacement of words or terms.Some had their structure modified to present an idea with simpler and more unambiguous expressions.
Despite adjustments and explanations, some items had to be eliminated at this stage.As evidenced in the participants' speeches, the lack of understanding of the lower strata was due to lack of knowledge of complex concepts and aspects, such as "architecture" and "learning".However, there was no damage to the item's content, as these aspects were evaluated in a general way in other items in the set, without compromising the breadth criterion.The same occurred with the items considered redundant in the face of their set, that is, with those that had aspects already covered in other items.In general, the changes made were essential to avoid measurement biases and to make the set of items clear and easy to understand, without compromising idiomatic, cultural, and semantic equivalences.
It should be noted that this entire evaluation process permeates the development of valid and reliable measurement instruments.Validated instruments are important not only for health assessment, but for scientific research and professional practice in the most distinct areas of knowledge.In this sense, validation studies help researchers and professionals to choose the best tool to ensure the quality of the results obtained (35) .

Study limitations
This study presents as a limitation the generalized analysis of the results, caused by the high number of items and specificity of the psychometric criteria evaluated.

Contributions to the Area
The aspects addressed in this study, in addition to helping to improve the nursing diagnosis "Sedentary Lifestyle", serve as a basis for studies aimed at building validated measurement instruments, which can provide important indicators for the care of patients according to their needs.In addition, the present work can equip physical education professionals, nurses and other health professionals, in a multidisciplinary approach, in the planning of interventions to promote physical activity for the health of populations in different contexts.

CONCLUSION
By understanding physical inactivity as an impediment to the healthy development of people and populations, vulnerability to physical inactivity involves aspects that have a negative impact on the biological, physical, social, and emotional dimensions of human life.A better understanding of the phenomenon requires the development of its measurement.
The items presented have adequate validity and appearance parameters and can subsidize the construction of evaluative instruments, which consider the subject's vulnerability and social vulnerability.It should be noted that this study refers to the initial stages of the construction process of a measurement instrument and that it is still necessary to carry out additional analyzes for the safe use of an instrument in the diagnosis of the population, allowing the elaboration of strategies to face physical inactivity.

Table 1 -
Criteria for changing and deleting items, according to CVI and psychometric parameters.Content Validity Index and judgment of items in the Subject Dimension CVI: Content Validity Index of Vulnerability to physical inactivity: evidence of content validity and response processes Pereira DS, Florêncio RS, Cestari VRF, Moreira TMM.Chart 1 -CVI: Content Validity Index; * p > 0.05 by binomial test for one sample; JPC: Judgment of psychometric criteria; + Unmodified item. 10 of Vulnerability

to physical inactivity: evidence of content validity and response processes
Pereira DS, Florêncio RS, Cestari VRF, Moreira TMM.Content Validity Index and judgment of items in the Social Dimension CVI: Content Validity Index; * p > 0.05 by binomial test for one sample; JCP: Judgment of psychometric criteria; + Unmodified item.10 ofVulnerability to physical inactivity: evidence of content validity and response processesPereira DS, Florêncio RS, Cestari VRF, Moreira TMM.

Item Items with changes after response processes Subject Dimension
-Subject Dimension;1, 4, 5, 6, 20, 26, 27, 30, 31, 32 -Social Dimension); in Items from the assessment of vulnerability to physical inactivity changed after evaluating the response processes: Subject and Social Dimension 6 In general, how would you rate your ability to perform daily physical activities?7 Have health professionals told you that you have a long-term health problem (high blood pressure, diabetes, asthma, heart problems, cancer…31 In your neighborhood and surroundings, do you have access to public/private structures that encourage the practice of physical activity (walking paths, sports courts, soccer fields, popular gyms, bike paths, exercise stations or skate parks)?32 In your neighborhood and surroundings, do you find private places conducive to the practice of physical activities (gym, fight, dance, swimming pool, club, active leisure center or similar establishments)?47 Do you have access to leisure activities in the region where you live?48 Do you have access to cultural activities in the region where you live? 49 Do you have access to public education in the region where you live? 10 of Vulnerability

to physical inactivity: evidence of content validity and response processes
Pereira DS, Florêncio RS, Cestari VRF, Moreira TMM.
[...] I think it's the same answer, because if it's in my neighborhood, it's close to my house.(Pessoa 32) Poorly preserved structure [36], it depends on the people, right?Sometimes yes, sometimes no.It depends on a lot [...]There are beautiful things and some ugly things [...] And this architecture, what is it?Are those tall buildings?(Person 03) Some people may not understand the meaning of the term [50].Furthermore, this question is not able to indicate the presence of a decrease in cognition or intellectual disability.(Person 45).